Originating in France in the 1980s, parkour is not easily defined. It is a practice of fluid movement, requiring no equipment but the body and the mind, as much cerebral as it is physical. Here, Cristian Lopez, a participant with Parkour Generations Americas, vaults a wall during a class called "Boston Weekend Wakeup" in Somerville.

Black Evitt, a 25-year-old Somerville native, has dedicated the last several years to studying parkour. An instructor with Parkour Generations Americas, Evitt is pictured with students (left to right) David Kovin, Daniel Abraham and Rachel Kelly as they warm up at the start of a class.

Inspired by military obstacle courses, parkour incorporates leaping, jumping, gymnastics, martial arts, breakdancing, and other movements to move from one point to another. David Kovin [pictured] ducks under a tree branch while running on a wall during class.

Class through Parkour Generations Americas are held at various parks throughout Somerville, the Cummings School on Prescott Street, various other elementary and middle schools, and at the Cambridge Center for Adult Education.

Rachel Kelly, a student with Parkour Generations Americas, is pictured as she crawls up some stairs.

Evitt said that parkour is social but not competitive . The discipline is about fitness and perseverance, as well as overcoming obstacles both in the physical world and in the mind. The instructor [left] along with students Daniel Abraham, Cristian Lopez and David Kovin lean against a wall together, catching their breath while waiting for another student to complete a drill on the stairs.

In November, Evitt started out with just a couple of classes for adults and kids in Somerville. Now, he’s teaching nearly a dozen, including after-school programs, which attract an age spectrum from 5 to 63. Here, he demonstrates a move for his students.

David Kovin, a student with Parkour Generations Americas, leaps from a wall to a light pole.

An active kid involved in soccer, swimming, and tennis while growing up in Somerville, Evitt discovered parkour as a French major at Davidson College in North Carolina.

Pictured: Evitt watches his students practice leaping over a snowpile onto a low wall.

Although Evitt’s done his fair share of boulder-scaling and streetscape leaping and dodging, he says it’s much more than a thrill-seeking cliché. The discipline has changed his perspective, how he sees and interprets things.

Daniel Abraham, a participant with Parkour Generations Americas, vaults a wall and lands on a light pole base.

Student Cristian Lopez, vaults over a railing as Evitt, (behind him) watches.

Evitt would like to get into performance with dance studios, circus troupes, and other acts, he said, and ultimately foster more of an exchange between the United States and Europe.